November 29, 2013

ESA Missions Will Seek To Understand The Evolution Of The Universe

The European Space Agency (ESA) announced today that the hot and energetic Universe and the search for elusive gravitational waves will be the focus of their next two large science missions.

Bridging fundamental astrophysics and cosmology themes, both topics will closely study the processes that are crucial to the large-scale evolution of the Universe and its underlying physics.

L2, the second large-class mission in ESA's Cosmic Vision science program, was selected for the "hot and energetic Universe" theme, which is expected to be pursued with an advanced X-ray observatory. ESA expects to launch L2 in 2028, where the mission will address two key questions: how and why does ordinary matter assemble into the galaxies and galactic clusters that we see today, and how do black holes grow and influence their surroundings?

Black holes lurk at the centers of almost all galaxies and are considered one of the key elements to understanding galaxy formation and evolution.

To study the gravitational Universe, the L3 mission will search for ripples in the very fabric of space-time created by celestial objects with very strong gravity – such as pairs of merging black holes.

Gravitational waves were predicted by Einstein's theory of general relativity. They have yet to be detected, but promise to open a completely new window to the Universe.

L3's launch is scheduled for 2034 and will require the development of a spaceborne gravitational wave observatory, or extreme precision ‘gravitometer’, an ambitious enterprise that will push the boundaries of current technology.

“ESA has an outstanding record for developing state-of-the art space observatories that have revolutionised our knowledge of how stars and galaxies were born and evolved,” says Alvaro Gimenez, ESA’s Director of Science and Robotic Exploration. “By pursuing these two new themes, we will continue to push back the scientific boundaries and unveil the mysteries of the invisible Universe.”

L2 and L3 selection process began in March 2013 with a call to the European science community, asking for suggestions for the next scientific themes to be pursued by the Cosmic Vision program's Large missions.

ESA received 32 proposals, which were assessed by a Senior Survey Committee. Following an extensive interaction with the scientific community, two major themes were recommended to the Director of Science and Robotic Exploration.

“We had a difficult task in deciding which scientific themes to choose from all of the excellent candidates, but we believe that missions to study the hot, energetic Universe and gravitational waves will result in discoveries of the greatest importance to cosmology, astrophysics, and physics in general,” says Catherine Cesarsky, chair of the Senior Survey Committee.

Activities to prepare for the missions will start very soon, despite the launches being over a decade away. ESA will issue a call for L2 mission concepts in early 2014 to solicit proposals for a next-generation X-ray observatory. The L3 mission will follow a similar procedure at a later date.

“We have opened up a new scientific roadmap for Europe today that will establish our leadership in this field for the next two decades while we develop and implement new technologies for these exciting missions,” adds Prof. Gimenez.